18 GHz Signals

[Shazlan]

Dear all,

I'm trying to put together a LabVIEW-based system that can generate and analyze signals up to 18 GHz. NI current Signal Generator and Analyzer cards can go only up to 2.7 GHz. I was told that there is a third party SG and SA that can go up to 18 GHz. My main concern is that I want to have control of the generator and analyzer through programming (LabVIEW), which I'm not sure is possible using any third party stuff. Any advice or suggestion is highly appreciated.


Shazlan

[Andy_Hinde]

Hello Shazlan,
What you probably heard was the announcement of a collaberation between NI, Phase Matrix, and BAE Systems to develop a 26.5 GHz RF Downconverter module in a PXI Express formfactor / bus. I am including a link to the press release below. This downconverter will be controllable via LabVIEW. However, the press release does not mention any plans for an upconverter for signal generation purposes so currently this partnership will only be addressing signal acquisition.

http://digital.ni.com/worldwide/bwcontent.nsf/websearch/f9288d2d843ba697862571ea007980a0


Regards,
Andy Hinde
National Instruments

[Shazlan]

Dear Andy, thanks for your reply.

Does anybody knows the status of this collaboration? Whether the product is still under development, in the testing phase, or out and ready to be used? If it is still not available, does anyone have an idea on how should I proceed with this. Suggestions are highly appreciated!

Thanks.


Shazlan

[Andy_Hinde]

Hi Shazlan,
I am looking into this and will reply as soon as I get some information on this.

Regards,
Andy Hinde
National Instruments

[Andy_Hinde]

Hi Shazlan,
I tracked down the following information:
NI is collaborating w/ Phase Matrix and BAE on the development of a 26 GHz PXI downconverter/analyzer product. 
-  Phase Matrix is developing the 26 GHz downconverter
-  NI is providing a PXI IF digitizer
-  BAE is porting some of their internally developed application S/W to the platform

For questions regarding the downconverter modue I'll have to refer you to Phase Matrix.

As far as timeline information, the realization of these products is quite a way out - unfortunately I can't be more specific than that in this public forum. In any case, I can tell you that these products will most likely not align with your timeframe at this point.

Hope this information helps.

Regards,
Andy Hinde
National instruments

[Tim_R]

Dear Shazlan,

There are numerous third party vendors for "RF equipment".  I would recommend the Rohde & Schwarz Spectrum Analyzers.  There are basically three classes of spectrum analyzer's offerd by Rohde & Schwarz, economy, general purpose & high performance.  I have used numberous Spectrum Analyzers over the years and I find the Rohde & Schwarz to be top of the line.  Currently using the FSU26 for about 3 years now.  Very, very nice instrument with lots of software plug ins for automatic analysis of common communications signals.

As for the Labview drivers you'll find available Labview drivers for most of the Rohde & Schwarz lineup.  I have used the CVI drivers with no problems.

I've never used the Rohde & Schwarz signal genertors.  I've used other brands.

I think you'll find that there aren't a lot of equipment vendors in the Ku signal band.  Rohde & Schwarz, Agilent, Boonton, Anritsu & I think Tektronix is in the game too just to name a few.

You sound like you are new to the Ku band test area.  Just remember this, always use high quality connectors and cables, measurement uncertainty can be the death of you test results.  I think Agilent offers a course in Microwave measurment fundamentals, I would recommend you attend something along these lines.

Sincerely,

Tim_R.

[Shazlan]

Dear Tim, Andy,
Thanks so much your replies.

Yes, you are right. I am new in the RF, Ku band areas. I've been dealing with data acquisition, on-the-ground and in-flight, previously. Now, the company is looking into 'radar jamming' as well as video telemetry kinda stuff.

Based on Andy's reply, I'll stop wishing for NI's products for my application for now. My fear of using third-party's hardwares and softwares is not to have the flexibility and total control on the system flow, automation... simply said, the system as a whole. This is especially true (as far as I am aware of, that is) if I were to integrate the system with other non-RF systems - control modules, DAQ, etc. I've done this before using all PXI stuff.

I've just went to Rohde & Schwarz's website to look at their spectrum analyzers and also, on LabVIEW drivers availability. I've went to Tektronix's and Agilent's some time back. What I am curious to know is what can one do with the "LabVIEW + FSU Spectrum Analyzer (SA) system for instance? Can the FSU SA somehow be programmed, by LabVIEW, for synchronization, triggering, etc? Also, to what extent of 'control' does the user has?

Perhaps Tim, or anybody else for that matter, can enlighten me on this. Or better, can someone give an example on how he/she has used LabVIEW along with third parties signal generators or spectrum analyzers?

Lastly, I really appreciate the help/'enlightenments' from you guys!!


Shazlan

[50ohmTerminator]

Hi Shazlan,

I have used R&S FSU to make measurements and have written some automated tests in LabVIEW. Although you do not the get the same level of control and ease of programming (compared to programming a PXI instrument) you should be able to get by. I would suggest downloading the LabVIEW drivers for the FSU and looking at the palette to see what functions are available to you. It takes a few tries to get the VIs in the right order as the drivers are not as intutive as the ones for PXI. I believe there are a couple of basic example programs that come with the driver.

Cheers!

[Tim_R]

Shazlan,

I'll have to take 50ohmterm's word on the Labview drivers.  I haven't used them.

However,  as for synchronization/triggering most equipment has the 10Mhz reference so that all instruments can be tied to the same reference source, usually required.  Most instruments can be setup on a "master/slave" scenario for the 10Mhz.  For the cost of a RG-58 cable it is highly recommended.

As for triggering there are a couple of different "trigger" inputs on most spectrum analyzers and trigger outputs on signal generators (hardware sync/triggering that is).  I use them a lot to "decode" pulsed signals (i.e. I gate the sampling of the spectrum analyzer to "discard" the parts of the pulse that I don't want to see.).  I have found that the high sweep speeds of modern spectrum analyzers will allow one to view most pulsed signals (i.e. > 10uSec or so, going from memory here).   Some of the newer spectrum analyzers will allow faster sweep speeds allowing possibly sub-microsecond pulse analysis.

I think Tektronix has a new Ku-band "real time" spectrum analyzer with a relatively wideband width and fast sweep times.  I have "played" with the 6 Ghz version of this instrument a few years ago.  If I remember correctly one can obtain "pulse phase" information from this a well, so long as the input bandwidth was wide enough.

Oh well, sounds like fun, good luck with it.

Tim_R.